Using the following example you can record the audio sound and play the recorded sound.
In this example im capturing the audio sound and encoding into the pcm format.


import java.io.*;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.microedition.media.*;
import javax.microedition.media.control.*;

public class VoiceRecordMidlet extends MIDlet {
private Display display;

public void startApp() {
display = Display.getDisplay(this);
display.setCurrent(new VoiceRecordForm());
}

public void pauseApp() {
}

public void destroyApp(boolean unconditional) {
notifyDestroyed();
}
}

class VoiceRecordForm extends Form implements CommandListener {
private StringItem message;
private StringItem errormessage;
private final Command record, play;
private Player player;
private byte[] recordedAudioArray = null;
public VoiceRecordForm() {
super("Recording Audio");
message = new StringItem("", "Select Record to start recording.");
this.append(message);
errormessage = new StringItem("", "");
this.append(errormessage);
record = new Command("Record", Command.OK, 0);
this.addCommand(record);
play = new Command("Play", Command.BACK, 0);
this.addCommand(play);
this.setCommandListener(this);
}
public void commandAction(Command comm, Displayable disp) {
if (comm == record) {
Thread t = new Thread() {
public void run() {
try {
player = Manager.createPlayer("capture://audio?encoding=pcm");
player.realize();
RecordControl rc = (RecordControl) player.getControl("RecordControl");
ByteArrayOutputStream output = new ByteArrayOutputStream();
rc.setRecordStream(output);
rc.startRecord();
player.start();
message.setText("Recording...");
Thread.sleep(5000);
message.setText("Recording Done!");
rc.commit();
recordedAudioArray = output.toByteArray();
player.close();
} catch (Exception e) {
errormessage.setLabel("Error");
errormessage.setText(e.toString());
}
}
};
t.start();

}
else if (comm == play) {
try {
ByteArrayInputStream recordedInputStream = new ByteArrayInputStream(recordedAudioArray);
Player p2 = Manager.createPlayer(recordedInputStream, "audio/basic");
p2.prefetch();
p2.start();
} catch (Exception e) {
errormessage.setLabel("Error");
errormessage.setText(e.toString());
}
}
}
}


link:http://j2mesamples.blogspot.com/